Network Protocols – Types and Uses

Network protocols are the set of rules that provide an easy, reliable, and secure way to transmit data between different devices on the same network. With the help of network protocols, users can easily communicate with people all over the world. Further, the devices through which users communicate with each other follow the network protocol rules for proper information exchange. These rules also make communication easy by dictating how to format, transmit, and receive data over the network. Thus, network protocols play an important role in modern digital communication.

In addition, users can use network protocols for both types of communication: digital and analog. They can also use them for accessing the internet, transferring files among devices, automating processes, and many other things. Many network protocols, such as wireless, wired, internet protocols, etc., can be used for communication. In this article, we will discuss network protocols in detail, such as how they work, different types of network protocols, etc. Let’s get started.

What Is a Network Protocol?

As we discussed earlier, a network protocol is a set of rules that describe various methods of data transmission between different devices over a network. All the devices, whether they are different in their structure and internal processes, can easily communicate over the network by following this set of rules. All other tasks that are necessary for effective communication over the web, such as authentication, error detection, and synchronization, are also handled by these protocols. In short, we can say that network protocols are necessary for the proper functioning of communication over the network.

Furthermore, you can not only communicate through network protocols but also manage and secure your data by following these protocols. Network management protocols such as ICMP, SNMP, etc., are used to monitor, manage, and maintain the network, and network security protocols such as HTTPS, SSL, etc., are used to secure the data in transit over the network. Also, network protocols make it easy for devices to interact with each other. Digital communication has now become easy and simplified by the different types of network protocols. They are now necessary tools for using the internet or any other digital communication.

How does Network Model Work?

The primary purpose of network protocols is to send and receive data over the network with proper security protection. To ensure it is done correctly, the network protocol is divided into different layers. Each layer is independent of all the other layers and is assigned to a particular task. They share data and also send and receive output and input from each other. There are typically two types of layered models used on which all the networking processes depend. The first one is the OSI model, and the second is the TCP/IP model. Here we are discussing the OSI model in detail.

OSI stands for Open Systems Interconnection, and this model was developed by the International Standard Organization (ISO). This model is divided into two layers: upper and lower. Each of these layers has a total of seven layers, and each layer performs a specific network task. The working of this model is done by dividing the whole task into seven smaller tasks, and then each of these tasks is assigned to seven different layers. All these layers work independently of each other. The list of these layers is given below:

1. a single physical layer

It is the lowest layer of the OSI model. This layer describes the way two or more devices can be connected physically to each other. It transmits the individual bits from one node to another node. This layer also defines the physical topologies and transmission modes.

2. Data Link Layer

This is the second layer of the OSI model and is responsible for the error-free data transfer from one node to another. This layer also ensures efficient and reliable communication between devices.

3. Layer 3 of the Network

This layer is responsible for the transmission of data from one host to another and provides the best suitable path to move data from the source to the destination. It also adds the source and destination addresses to the header of the frames.

4. Transport Layer 4

This layer ensures that all the messages or data are transmitted in the correct order between nodes and is responsible for the end-to-end delivery of the complete message. It also converts the data into smaller units known as segments.

5. Layer 5 of the Session

This layer is used to establish, use, and terminate a connection during communication over the network. Maintenance of these sessions and other security tasks are also done by this layer. It acts as a dialogue controller between two processes and also allows them to add checkpoints to the data.

6. Presentation Layers

This layer acts as a data translator for a network, converting the data from one format to another. You can also call this layer the “Translation” layer. All the data compression and encryption work is also done in this layer.

7. Application Layer

This layer is also called the Desktop layer, and it serves as a window for the users and all application processes over the network. It allows users to access and manage the files on a remote computer. This layer also provides mail services such as email forwarding and storage.

Classification 0f Network Protocols

After discussing the working of network models, let’s discuss different types of protocols used over the network.

Application Layer Protocols

1. DHCP

DHCP stands for Dynamic Host Configuration Protocol. Located at the application layer of the networking model, this protocol is based on the client-server architecture. The DHCP clients request information from the DHCP servers, and the servers then relay the requested information back to the clients. The main purpose of DHCP is to assign different devices on a network unique IP addresses. It maintains a list of IP addresses that are assigned to different devices. In addition, it provides other network addresses such as subnet masks, router addresses, DNS addresses, etc.

Advantages:

1. This protocol makes it easy to assign a unique IP address to a particular device.
2. It saves time and workload for the network administrators.
3. By using this protocol, the configuration is made much simpler for all types of networks, such as large or medium.
4. Also, the implementation of this protocol does not require any additional cost.
5. It provides excellent support to mobile users because they can get the new valid configurations automatically if there is any change in their network.

Disadvantages:

1. The main disadvantage of this protocol is that it does not provide any secure mechanism for the authentication of the client.
2. When a new IP address is assigned to the client, the machine name does not change in this protocol.
3. If the network only has one configured DHCP server, the DHCP server can be a single point of failure.
4. Also, if the DHCP server is not present on the network, then it is not possible for the client to access the network.
5. In this protocol, it is necessary to configure the relay agent with the IP addresses of the DHCP server to ensure the travel of the DHCP packets over the network.

2. DNS

DNS stands for Domain Name System and is based on the client-server model. This protocol uses a hierarchical domain-based naming scheme to translate the domain names of the devices over the network to numerical IP addresses. This protocol’s DNS server is configured with Fully Qualified Domain Names (FQDN), and all IP addresses are mapped to their email addresses.It also supports other protocols such as TCP and UDP. The DNS server uses UDP port 53 for its work.

Advantages:

1. This protocol makes it easy to use the internet because it remembers all the IP addresses.
2. It also offers high-speed connections, so individuals and organisations can take advantage of its speed easily.
3. DNS also provides enhanced security features for home and work connections.
4. With the help of DNS, search engines can easily categorise and archive information.
5. Stability is another advantage of this protocol because if there is any change in the IP address of a system, then it is automatically updated by the DNS system.

Disadvantages:

1. The major disadvantage of this protocol is that the client information can be easily manipulated by hackers.
2. Two DNS attacks are another disadvantage of this protocol. In this type of attack, the original IP address of the site is replaced with a fake address by the hackers.
3. If the master server of this system breaks down, then it becomes difficult for the client to access the webpage on the network.
4. Because of the distributed nature of this protocol, troubleshooting is also difficult.

3. FTP

Another application layer protocol is FTP, which stands for File Transfer Protocol. This protocol is used to transfer files from one location to another. Both binary and text files can be transmitted by using this protocol. Before sharing these files, a connection is established by providing a username and password. One connection is established for control information, and the other is for data. Ports 21 and 20 are used for the control connection and data connection, respectively.

Advantages:

1. The very first advantage of using this protocol is that it is very simple to implement and use.
2. There is also no size limitation on transferring files.
3. FTP transfers files at breakneck speed across the network.
4. This protocol also provides the auto-backup facility.
5. Also, it allows you to transfer two or more files at the same time.
6. You can also connect to the server using FTP from different operating systems without any issue.

Disadvantages:

1. The biggest disadvantage of using this protocol is more memory consumption and programming effort.
2. It is required to send the files, usernames, and passwords in clear text format for this protocol.
3. An integrity check on the receiver side is also not performed.
4. Data encryption facilities are also not provided by all FTP servers.
5. Stronger passwords are always recommended in this protocol because hackers can easily guess them otherwise.

4. HTTP

“HTTP stands for Hypertext Transfer Protocol. This protocol is also based on a client-server architecture. It is a type of stateless protocol that follows a particular set of rules and standards to transfer the data between the clients and the web server. It uses TCP/IP and UDP protocols. In this protocol, an HTTP request is sent by the client in the browser, and then the server sends the requested information to the client in the form of web pages. You can use this protocol for normal web browsing over the network.

Advantages:

1. HTTP is a flexible protocol because all the additional capabilities that are needed by an application, such as Flash Player, Acrobat Reader, etc., can be easily included in it.
2. Assures the integration of the data and information on both ends of this protocol.
3. Each file in HTTP is downloaded over an independent connection, and after downloading, each link is closed by the protocol. This feature enhances the security of the files.
4. The CPU and memory usage in this protocol is also very low as compared to other protocols.
5. Also, it is easy to follow and implement because it is coded in plain text.

Disadvantages:

1. Data privacy is a major problem in HTTP because hackers can easily see the contents of the webpage.
2. This network protocol isn’t optimised for mobile phones either.
3. The connection is not closed by the client after receiving all the data that is needed. Therefore, the server will not be available during that time.
4. Power consumption is very high in this protocol because HTTP uses many system resources.

5. IMAP

IMAP stands for Internet Message Access Protocol and is used to access emails through a web browser. It also allows users to make some changes to the content of the email without downloading it. Also, all the emails can be perfectly synchronized by using this protocol because they are saved in the cloud rather than on the computers. Users can also customize the mail server in different folders according to their needs. This protocol uses port 143 to communicate over the network.

Advantages

1. The main advantage of using this protocol is that users can easily access all the emails from any device because they are stored on the mail servers.
2. The local storage is utilized correctly because all the emails are on the server.
3. Migration is also effortless from one computer to another in this protocol because users do not have to download all the messages again.
4. If there is any problem occurring on the user’s personal computer, then it does not affect the email servers because they work independently.
5. Also, all the information is exchanged securely in this protocol because it supports other technologies such as TLS/SSL protocols.

Disadvantages

1. A lot of old useless information is stored in this protocol which further increases the cost of the server.
2. This protocol downloads the information more slowly than other protocols such as SMTP.
3. If you don’t have an active internet connection, then you can not access the emails.
4. It is also very complex to maintain this protocol.

6. POP & POP3

POP stands for Post Office Protocol. There are mainly two protocols used for accessing emails. POP is one of them. It is used by users to receive emails from mail servers. Clients can receive the emails through a TCP/IP connection. When the emails are downloaded by the clients, then they are removed from the email servers. POP3 is the enhanced version of POP. It is a simple and popular protocol. Almost all email clients support POP3 today. Also, this protocol allows the clients to access the emails offline.

Advantages:

1. This protocol is very easy to configure and use.
2. Also, because they have already been downloaded, downloaded attachments can be opened very quickly in this protocol.
3. This protocol is also supported by all clients.
4. Furthermore, very little storage space is required in this protocol.
5. Another advantage is that this protocol allows the clients to read the emails offline.

Disadvantages:

1. The main disadvantage of using this protocol is that if your emails are not configured, then you cannot access them from another computer.
2. Email attachments can contain viruses because they are stored on local machines.
3. Also, email folders that you downloaded from the mail servers can be corrupted, and you can lose them all at once.
4. Lastly, it is a difficult process to transfer the mail folders from one device to another.

7. SMTP

SMTP stands for Simple Mail Transfer Protocol and is another application level protocol. The protocol is used to send messages over the Internet. It’s important to note that you can use SMTP for sending emails, but not for receiving them from the mail server. SMTP also verifies successful email transmission. If the email cannot be successfully delivered, the message is sent back to the sender. Using this protocol, you can also transfer emails from one server to another.

Advantages:

1. The very first advantage of using this protocol is that it is an open standard protocol, so any network application can easily use it for sending emails.
2. Also, it is a very reliable protocol with well-defined rules.
3. Simplicity is another advantage of using SMTP because clients have to give their credentials only once and then they can use them easily.
4. It is open-standard in nature and is adopted by almost all network applications, ensuring no compatibility issues with using this protocol.
5. If there is any failure in sending emails, then the clients are notified with a proper explanation of the reason for the loss.

Disadvantages:

1. One major disadvantage of using SMTP is that you have to convert binary files into text files before sending them.
2. Also, you can send emails of a specific length within this protocol. Otherwise, SMTP servers can reject them.
3. It is an insecure protocol and can be hacked easily.
4. Lastly, ports that are commonly used for SMTP can be blocked by some firewalls.

8. TELNET

TELNET stands for Teletype Network and is based on the client-server model. It is the Terminal Network Protocol that is used to connect computers remotely to the network. Users can use this protocol to connect to any other computer remotely by giving their usernames and passwords and can easily access the software and data of another computer. The process of connection is very simple, so very much time and effort for users are saved. TELNET connects using the TCP protocol.

Advantages:

1. You can use this protocol to send and receive data from one computer to another without any difficulty.
2. This protocol is applicable to any type of operating system.
3. Also, you do not have to go to another computer to collect data and other information, so most of your time is saved.
4. The compatibility features of this protocol make it flexible as well.
5. User authentication is also supported by this protocol.

Disadvantages:

1. The main disadvantage of using this protocol is that your user name and password are not encrypted, so there is a high chance of hacking.
2. Because of the slow typing speed of this protocol, it is expensive to use.
3. Also, if you want to run GUI-based tools on this protocol, then it is not possible because it is a character-based protocol.
4. Lastly, the absence of an encryption technique makes this protocol less secure.

Session Layer Protocol

9. RPC Remote Procedure Call

RPC is the session layer protocol and is also called a function call or subroutine call. By using this protocol, users can request a service from another programme on a remote computer. The user who requests a programme is called the client, and the programme on another computer is called the server. So this protocol is also based on a client-server architecture. Moreover, multiple RPCs can be performed at the same time because many lightweight processes are used in this protocol that share the same address space. For communicating with another program, RPC uses other protocols as well, such as UDP and TCP/IP.

Advantages

1. This protocol supports process-oriented and thread-oriented models that make communication easy for the programs.
2. Also, there is minimal effort required to rewrite or re-develop the codes.
3. You can use RPC in the local environment as well as in a distributed environment.
4. Abstraction is another principal advantage of RPC because the process of message-passing over the network is hidden from the users.
5. Furthermore, the semantics of RPC are straightforward, so you can quickly develop distributed systems.

Disadvantages:

1. If you are transferring a large amount of data over the network, then it is not recommended to use RPC because of the different execution environments of the clients and servers.
2. It also increases the cost of the scheduling because of the high number of context switches.
3. It cannot solve the vast majority of distribution and creation issues.
4. There is also a high chance of failure in RPC as there are many other machines and programmes involved in the communication process.
5. Lastly, RPC is not flexible and also does not have any uniform standards to use.

Transport Layer Network Protocol

10. TCP

“TCP is an abbreviation for Transmission Control Protocol. It is a type of communication protocol used to connect various devices across a network. It is a dependable network protocol because it can recover from failures. It also allows for end-to-end communication. TCP also specifies how messages are gathered into small packets. This protocol also specifies how a specific computer should be connected to a network and how data is transmitted between devices.

Advantages

1. TCP is an open standard protocol; that’s why it allows establishing connections on different types of computers.
2. Also, it allows you to work from different operating systems.
3. Duplication is not allowed because the sequence numbers given by TCP to different packets are unique.
4. Many network routing protocols are supported by TCP.
5. TCP also guarantees the in-order delivery of packets to their destination.

Disadvantages

1. TCP is an open standard protocol; that’s why it allows establishing connections on different types of computers.
2. Also, it allows you to work from different operating systems.
3. Duplication is not allowed because the sequence numbers given by TCP to different packets are unique.
4. Many network routing protocols are supported by TCP.
5. TCP also guarantees the in-order delivery of packets to their destination.

11. UDP

“UDP stands for “User Datagram Protocol.” It is a connectionless protocol, which means that when the data is transferred between client and server, the connection is not established by UDP. This protocol is mainly used for broadcasting messages, and data is transferred directly over the network at a very fast speed. Furthermore, UDP is the best-suited protocol if the data is transferred in only one direction. You can also use this protocol in streaming and multicast applications. Packets used in UDP are very small in size, further reducing their processing time.

Advantages

1. The main advantage of using UDP is that you are not restricted to a connection-based communication model, so the startup time is very small for this protocol.
2. UDP is a useful protocol for multicast and broadcast transmissions.
3. Also, the packet size is small in UDP, so less memory is required, and processing also becomes fast.
4. This protocol uses the checksum method with all the packets to find any errors in transmission.
5. The speed of UDP also increases because of the absence of the acknowledgment field.

Disadvantages:

1. It is an unreliable protocol.
2. There is no functionality to ensure that data is being received or not.
3. The error control mechanism of this protocol is also not good.
4. Congestion control methods are also not present in UDP.
5. Lastly, routers are careless in terms of handling this protocol properly.

Network Layer Protocol

12. IP Internet Protocol

The Internet Protocol (IP) is a network layer protocol that contains all of the addressing and control information for packets sent across the network.The host can be on the same or different network and is assigned a 32-bit address. This address consists of two parts: the network number and the host number. IP describes how the network layer works and interacts with other layers in the system. All the packets of information are kept in sequence in this protocol. Moreover, you can add new networks easily without any interruption to current services.

Advantages:

1. The 1 Internet Protocol supports many other routing protocols.
2. It allows cross-platform communications, so you can use it on different operating systems and devices.
3. This protocol assigns a unique address to each device over the network, so identification of every device is also very easy by using it.
4. It is an open standard and can be used by an organisation or individual.
5. Also, all mechanisms such as error control, flow control, and congestion control are used by this protocol.

Disadvantages:

1. Just like TCP, this protocol is also very complicated to set up and manage.
2. Replacing a protocol is also not an easy task.
3. There is no guarantee of the delivery of packets.
4. With this protocol, all the network communication is done through a DNS server, and hackers can easily exploit it.

13. IPv6

IPv6, like Internet Protocol, is a network layer protocol that contains all of the addressing and control information for all packets transmitted over the internet.The basic difference between these two protocols is that IP assigns a 32-bit address to a device, but IPv6 assigns 128 bits to the device. The main reason for developing this protocol is to remove all the address exhaustion issues of IP. The new IP addresses used in IPv6 fulfil the need for more address spaces. This protocol is also called Internet Protocol Next Generation. Moreover, the auto-configuration feature of this protocol provides a great benefit to network administrators.

Advantages:

1. In IPv6, path allocation is done by the Maximum Transmission Unit protocol, which ensures the efficient routing of packets.
2. Because there is more address space available in IPv6, network capacity is also increased.
3. Multicast addressing is used in this protocol, and you can easily send large data packets over the network.
4. Also, the flow label field used in IPv6 helps identify the packets of the same flow.
5. IPv6’s data integrity and security features increase its popularity.

Disadvantages:

1. Shifting from IPv4 to IPv6 is a slow and laborious process.
2. If you want to communicate from an IPv4 device to an IPv6 device, then you have to use an intermediate technology for this.
3. Also, this protocol has readability issues because the subnetting feature is difficult to understand.
4. Manually assigning new IP addresses is a difficult task because the addresses are very long and contain letters and numbers.

14. ICMP

“ICMP stands for “Internet Control Message Protocol.” This protocol is used to generate error messages if there is any problem with delivering the packets over the network. In the event of any problem regarding the transmission of packets, ICMP is used as a router to communicate with the source of the data packet. Also, all the queries related to the management of packets are resolved by this protocol. Moreover, it helps the network administrators diagnose the network issues. ICMP is used in both protocols, IPv4 and IPv6.

Advantages:

1. ICMP is the best protocol to diagnose networking issues.
2. Further, in the case of any issue, this protocol sends error messages such as “source route failed” or “source quench,” etc.
3. ICMP also provides direct communication in the network area.
4. If a data packet remains undelivered, then ICMP reports back all the details to the host to specify where the transmission has failed.
5. You can troubleshoot any internet connection using tools such as Ping and Traceroute.

Disadvantages:

1. ICMP is only used to send error messages; it cannot be used to send data packets over a network.
2. Also, you cannot use this protocol to share the resources of the client’s computer.
3. Network traffic is also increased with the increased number of ICMP messages.
4. Security is a major concern in this protocol. Attackers can easily discover the systems to target in the future.

Data Link Layer Protocol

15. ARP Address Resolution Protocol

The Address Resolution Protocol is a communication protocol that is used to find the Media Access Control (MAC) address of a device from a given IP address. It is necessary to find the MAC address of a device because, without it, you cannot connect a device with another in the local area network.

ARP converts the given 32-bit IP address to a 48-bit MAC address. When the conversion is done, ARP sends this MAC address to the source device. After that source, the device keeps that address in the table, and if the MAC address is not found in the table, then the source device generates an ARP request message. Further, this protocol is used when you want to connect a network device to another network device on a local area network.

Advantages:

1. By using ARP, you can easily find the MAC address of a device from its IP address.
2. Also, this protocol helps the host do mapping between IP addresses and hardware addresses.
3. In the ARP table, all the MAC addresses are saved and can be used for future communication.
4. It also saves your efforts and time because you do not need to configure the end nodes to find the MAC addresses.
5. Further, you can use any ARP resolution technique to ease your work, such as table lookup, dynamic, and closed-form computation.

Disadvantages:

1. ARP is used only for finding the MAC address of a given IP address. You can not use it for sending or receiving messages over the network.
2. Also, this protocol can be used only on local area networks or Ethernet.
3. ARP attacks such as ARP spoofing can occur. This type of attack can lead to the sniffing of data frames.
4. Another type of ARP attack, ARP denial of service, may occur, halting all network traffic.

16. SLIP Serial Line IP

Serial Line Internet Protocol (SLIP) is a data link layer protocol that works with the TCP/IP protocol suite. Point-to-point serial connections are established in this that are further used in serial ports and routers. Devices that are connected to the internet service providers place their requests, and after resolving all the requests, the ISP sends those requests back to the clients through serial lines. Furthermore, when using SLIP for communication, both ends must know their IP addresses.Also, there is no limitation on packet size in this protocol.

Advantages:

1. The biggest advantage of using this protocol is that it is very simple and easy to implement.
2. Two fewer wires are required, so the cost is also less.
3. Data is transferred synchronously in this protocol.
4. Also, you can easily use this protocol on microcontrollers.
5. You can also transmit large packet sizes.

Disadvantages

1. SLIP does not provide any mechanism for error detection or error correction.
2. Also, there is no authentication mechanism in this protocol.
3. Dynamic allocation of IP addresses is not possible in SLIP.
4. If you have a slow-speed internet connection, then it is not a good choice to use SLIP.
5. Lastly, you cannot use it for multiple protocol functionalities, and only one protocol can run at a time on SLIP lines.

Wrapping Up

We went over network protocols in depth in this article. These protocols are critical in network communication because they define the rules of communication. All network devices, regardless of architecture, can be easily connected using network protocols. Furthermore, these protocols assist network administrators in detecting errors during communication. Communication becomes more accurate and efficient with the help of the various mechanisms used in these protocols.

Moreover, network protocols are integrated into the topology, and you can use more than one protocol in the same topology. The set of cooperating network protocols is called a protocol suite. Further, there are thousands of network protocols available today that can do plenty of tasks such as automation, authentication, compression, error correction, error handling, routing, and many more. You can use any of them according to your work needs. We can also say that modern communication is not possible without these protocols. I hope this article gives you a better understanding of all the above-discussed topics.